We just returned from a cruise on the Dawn Princess where we opted for Personal Choice Dining. Although we left the auto tip on, we opted to give our dining room waiter and his assistant more because we reserved a table with them for the ENTIRE WEEK of our cruise. They were very attentive and went out of their way to make sure we enjoyed our dining experience. The last night of the cruise my husband handed them both envelopes which contained a note stating that we left the auto tip on, and the enclosed was an additional tip for the exceptional service they provided to us. Had we opted for a different dining room waiter and assistant every night, I don't think we would have tipped additional (unless the service was absolutely extraordinary). Enjoy your cruise.